Can an explosive storage box acceptance rely on the supplier's inspection sheet?

Answer: No. It is a self-check stamped by the seller. Acceptance needs independent sampling, and critical items need third-party support.

Is the sampling ratio set by lot size or by order value?

Answer: By lot size, never by value. Split deliveries count as separate lots.

Can a third-party report older than 24 months still be used?

Answer: Not as the governing document. Use it as background, add a sampling retest, then let the new report govern.

How deep a scratch fails inspection?

Answer: Over 30 mm long, over 0.2 mm wide, or three or more 10 mm scratches on one face.

Can a concession lot be stored with conforming stock?

Answer: No. It is stored and numbered apart, with the price adjustment and retest date recorded.

Explosive Storage Box Acceptance: Test Items and Verdicts

Quick answer: Acceptance rests on three decisions: which document governs the verdict, how test items are graded, and how many units to sample. Critical items fail a lot on one defect, major items run at AQL 1.0, minor items can pass with a price cut.

Where an Explosive Storage Box Acceptance Starts
Visual Checks and Sampling Ratios
Dimensional Verdicts and Fit Tolerance
Reading and Retaining Test Reports
Verdicts and Disposition
FAQ

1. Where an Explosive Storage Box Acceptance Starts

Most disputes begin with the wrong document: buyers reach for a general standard, then hunt for a clause that fits. The order that works is contract annex, drawing and signed sample, general standard only where those are silent.

Three conditions apply before the first measurement: a signed sample of three units from one batch and mould, tools inside a 12-month calibration window, and a case rested four hours at 23 ± 5 °C.

Grade	Test items	Sampling	Failure rule
Critical	Latch force, thinnest wall, seal contact, handle load	3 units per lot	One defect rejects the lot
Major	Internal length, lid gap, flatness, colour	AQL 1.0	Above the limit rejects the lot
Minor	Scratches, flash, print, label	AQL 2.5	Price adjustment allowed

2. Visual Checks and Sampling Ratios

Visual inspection needs reproducible conditions: D65 light, 500 lx minimum, 500 mm viewing distance, sight line at 45 degrees. Without them, slight scratch means whatever the inspector decides. Fix the scale: scratches under 10 mm long and 0.2 mm wide, two per face at most; anything over 30 mm fails; flash above 0.3 mm counts as major.

Green explosive storage boxes stacked three layers high on a timber pallet on a warehouse floor, two rows of three per layer, lids facing up

Sample an explosive storage box lot this way: up to 500 units take 8, up to 1,200 take 13, above that 20, doubled after a rejection. Draw from top, middle and bottom of the pallet, or every stacking bruise slips through. Log resin batch, density and melt index alongside; a regrind share above 20 percent drags wall uniformity and low-temperature impact down.

3. Dimensional Verdicts and Fit Tolerance

Dimension checks are not a pass-or-fail switch. The middle verdict, accept with concession, stops a half-millimetre deviation from returning a lot while still blocking anything that disturbs assembly or sealing.

Item	Nominal	Pass band	Concession band
Internal length	820 ± 2.0 mm	818.0 to 822.0 mm	817.0 to 818.0 mm
Lid gap	1.5 mm max	0.3 to 1.5 mm	1.5 to 2.0 mm
Thinnest wall	6.0 mm nominal	5.4 mm minimum	5.2 to 5.4 mm

Measure lid gap with a feeler gauge every 200 mm around the rim, worst point recorded. Above 1.5 mm it usually means under-torqued latches or a misaligned parting line, so adjust and re-measure before writing a verdict. Wall thickness uses six points, four corners plus each long-side midpoint, sliced and ultrasonic readings within 0.1 mm.

4. Reading and Retaining Test Reports

A report that can carry a verdict survives four questions: is the addressee the producer of this lot, do sample number and model match the contract word for word, are temperature, drop height, stacking load and hold time stated, and is there a signed verdict?

Validity runs 24 months, only while resin grade, wall thickness and latch model stay unchanged; change one and the old report lapses. Keep paper and scan five years, one physical unit per lot for 12 months with lot, mould and date on the tag.

5. Verdicts and Disposition

Three verdicts exist: accept, accept with concession, reject; a fourth path, rework then reinspect, covers replaceable parts.

Verdict	Trigger	Action	Record
Accept	No critical defect, majors within limit	Label and store by lot	Kept five years
Concession	Minors only, seal and load unaffected	3 to 8 percent price cut	Retest in 30 days
Reject	Two critical defects or no report	Return the lot	Notice in 7 working days

Tightened inspection belongs in the contract: after a first rejection the next explosive storage box lot is sampled at double the count and one AQL step tighter, back to normal after three clean lots.

Conclusion

An acceptance standard earns its keep when the same case yields the same verdict in two hands. Fix the document order, grade the test items, sample by lot, keep a concession band, and hold reports and samples for their stated terms. Done that way, every explosive storage box acceptance becomes defensible.

This article discusses only the container (case body) side of specifications and design intent, and does not cover any handling, loading or use of the contents.